Title: Numerical modelling of non-Newtonian fluids in a mechanical flotation cell

Authors: C.W. Bakker, C.J. Meyer, D.A. Deglon

Addresses: Centre for Minerals Research, Department of Chemical Engineering, University of Cape Town, Private Bag X3, Rondebosch, Cape Town, South Africa. ' Centre for Research in Computational and Applied Mechanics, University of Cape Town, Private Bag X3, Rondebosch, Cape Town, South Africa. ' Centre for Minerals Research, Department of Chemical Engineering, University of Cape Town, Private Bag X3, Rondebosch, Cape Town, South Africa

Abstract: This paper investigates the formation of a cavern around the impeller of a mechanical flotation cell agitating a highly non-Newtonian mineral slurry. Caverns consist of yielded fluid surrounded by stagnant fluid and are known to form in non-Newtonian yield-stress fluids. Two single phase non-Newtonian fluids were modelled with rheologies equal to experimentally determined mineral slurries, using the Herschel-Bulkley non-Newtonian model. Findings showed a cavern forms around the stator, with its size depending on slurry yield stress, and that the Shear-Stress Transport (SST) k − ω turbulence model predicted the cavern most accurately.

Keywords: CFD; computational fluid dynamics; stirred tanks; non-Newtonian fluids; mineral slurries; caverns; flotation cells; impellers; modelling; slurry yield stress; shear-stress transport.

DOI: 10.1504/PCFD.2009.027361

Progress in Computational Fluid Dynamics, An International Journal, 2009 Vol.9 No.6/7, pp.308 - 315

Published online: 21 Jul 2009 *

Full-text access for editors Full-text access for subscribers Purchase this article Comment on this article